Stacked power amplifiers with dc current reuse

ABSTRACT

Apparatus and the methods for stacked power amplifiers are provided. In certain embodiments, a mobile device includes a transceiver that generates a first radio frequency input signal and a second radio frequency input signal, and a front end system including a stacked power amplifier that receives power from a power high supply voltage and a power low supply voltage. The stacked power amplifier includes a first power amplifier that amplifies the first radio frequency input signal and a second power amplifier that amplifies the second radio frequency input signal. The first power amplifier and the second power amplifier are electrically connected in a stack between the power high supply voltage and the power low supply voltage and operate with a shared DC bias current.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority under 35 U.S.C. § 119 of U.S. Provisional Patent Application No. 63/199,880, filed Jan. 29, 2021 and titled “STACKED POWER AMPLIFIERS WITH DC CURRENT REUSE,” which is herein incorporated by reference in its entirety.

BACKGROUND Field

Embodiments of the invention relate to electronic systems, and in particular, to power amplifiers for radio frequency (RF) electronics.

Description of the Related Technology

Power amplifiers are used in radio frequency (RF) communication systems to amplify RF signals for transmission via antennas. It can be important to manage the power of RF signal transmissions to prolong battery life and/or provide a suitable transmit power level.

Examples of RF communication systems with one or more power amplifiers include, but are not limited to mobile phones, tablets, base stations, network access points, laptops, and wearable electronics. Power amplifiers provide amplification to RF signals, which can have a frequency in the range from about 30 kHz to 300 GHz, such as in the range of about 410 MHz to about 7.125 GHz for fifth generation (5G) communications using Frequency Range 1 (FR1) or in the range of about 24.25 GHz to 52.6 GHz for 5G communications using Frequency Range 2 (FR2).

SUMMARY

In certain embodiments, the present disclosure relates to a mobile device. The mobile device includes a transceiver configured to generate a first radio frequency input signal and a second radio frequency input signal, and a front end system including a stacked power amplifier configured to receive power from a power high supply voltage and a power low supply voltage. The stacked power amplifier includes a first power amplifier configured to amplify the first radio frequency input signal and a second power amplifier configured to amplify the second radio frequency input signal. The first power amplifier and the second power amplifier are electrically connected in a stack between the power high supply voltage and the power low supply voltage and are configured to operate with a shared DC bias current.

In various embodiments, the first power amplifier includes a positive supply terminal connected to the power high supply voltage and a negative supply terminal, and the second power amplifier includes a positive supply terminal connected to the negative supply terminal of the first power amplifier and a negative supply terminal connected to the power low supply voltage. According to a number of embodiments, the first power amplifier includes a first amplification field-effect transistor and a first cascode field-effect transistor connected in series between the negative supply terminal and the positive supply terminal of the first power amplifier, and the second power amplifier includes a second amplification field-effect transistor and a second cascode field-effect transistor connected in series between the negative supply terminal and the positive supply terminal of the second power amplifier. In accordance with several embodiments, the first amplification field-effect transistor includes a gate configured to receive the first radio frequency input signal, and the second amplification field-effect transistor includes a gate configured to receive the second radio frequency input signal. According to some embodiments, the stacked power amplifier further includes a decoupling capacitor connected between a source of the second amplification field-effect transistor and the power low supply voltage. In accordance with a number of embodiments, the stacked power amplifier further includes a first degeneration inductor connected between a drain of the first cascode field-effect transistor and a source of the second amplification field-effect transistor, and a second degeneration inductor connected between a drain of the second cascode field-effect transistor and the power high supply voltage.

In several embodiments, the mobile device further includes an antenna array including a first antenna configured to transmit a first radio frequency output signal provided by the first power amplifier and a second antenna configured to transmit a second radio frequency output signal provided by the second power amplifier. According to various embodiments, the antenna array is configured to radiate a transmit beam based on the first radio frequency output signal and the second radio frequency output signal.

In some embodiments, the first radio frequency input signal is a first multiple-input multiple-output signal and the second radio frequency input signal is a second multiple-input multiple-output signal.

In various embodiments, the first radio frequency input signal is a first carrier aggregation signal and the second radio frequency input signal is a second carrier aggregation signal.

In a number of embodiments, the first radio frequency input signal and the second radio frequency signal are each a fifth generation signal.

In several embodiments, the first radio frequency input signal is a fifth generation signal and the second radio frequency input signal is a fourth generation signal.

In some embodiments, the first radio frequency input signal is a first millimeter wave signal and the second radio frequency input signal is a second millimeter wave signal.

In certain embodiments, the present disclosure relates to a packaged module. The packaged module includes a package substrate, and a semiconductor die attached to the package substrate and including a stacked power amplifier configured to receive power from a power high supply voltage and a power low supply voltage. The stacked power amplifier includes a first power amplifier configured to amplify a first radio frequency input signal and a second power amplifier configured to amplify a second radio frequency input signal. The first power amplifier and the second power amplifier are electrically connected in a stack between the power high supply voltage and the power low supply voltage and are configured to operate with a shared DC bias current.

In some embodiments, the first power amplifier includes a positive supply terminal connected to the power high supply voltage and a negative supply terminal, and the second power amplifier includes a positive supply terminal connected to the negative supply terminal of the first power amplifier and a negative supply terminal connected to the power low supply voltage.

In various embodiments, the packaged module further includes an antenna array formed on the package substrate, the antenna array including a first antenna configured to transmit a first radio frequency output signal provided by the first power amplifier and a second antenna configured to transmit a second radio frequency output signal provided by the second power amplifier. According to a number of embodiments, the antenna array includes a plurality of patch antennas formed on a surface of the package substrate. In accordance with several embodiments, the antenna array includes a plurality of edge-fired antennas formed on an edge of the package substrate.

In certain embodiments, the present disclosure relates to a method of radio frequency signal amplification in a mobile device. The method includes powering a stacked power amplifier with a power high supply voltage and a power low supply voltage, amplifying a first radio frequency input signal using a first power amplifier of the stacked power amplifier, and amplifying a second radio frequency input signal using a second power amplifier of the stacked power amplifier, with the first power amplifier and the second power amplifier electrically connected in a stack between the power high supply voltage and the power low supply voltage. The method further includes biasing the first power amplifier and the second power amplifier with a shared DC bias current.

In some embodiments, the method further includes beamforming a transmit beam using an antenna array, including transmitting a first radio frequency output signal provided by the first power amplifier on a first antenna of the antenna array and transmitting a second radio frequency output signal provided by the second power amplifier on a second antenna of the antenna array.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of one example of a communication network.

FIG. 2A is a schematic diagram of one example of a communication link using carrier aggregation.

FIG. 2B illustrates various examples of uplink carrier aggregation for the communication link of FIG. 2A.

FIG. 2C illustrates various examples of downlink carrier aggregation for the communication link of FIG. 2A.

FIG. 3A is a schematic diagram of one example of a downlink channel using multi-input and multi-output (MIMO) communications.

FIG. 3B is schematic diagram of one example of an uplink channel using MIMO communications.

FIG. 3C is schematic diagram of another example of an uplink channel using MIMO communications.

FIG. 4A is a schematic diagram of one example of a communication system that operates with beamforming.

FIG. 4B is a schematic diagram of one example of beamforming to provide a transmit beam.

FIG. 4C is a schematic diagram of one example of beamforming to provide a receive beam.

FIG. 5A is a schematic diagram of a stacked power amplifier according to one embodiment.

FIG. 5B is a schematic diagram of a stacked power amplifier according to another embodiment.

FIG. 5C is a schematic diagram of a stacked power amplifier according to another embodiment.

FIG. 5D is a schematic diagram of a stacked power amplifier according to another embodiment.

FIG. 5E is a schematic diagram of a stacked power amplifier according to another embodiment.

FIG. 5F is a schematic diagram of a stacked power amplifier according to another embodiment.

FIG. 5G is a schematic diagram of a stacked power amplifier according to another embodiment.

FIG. 5H is a schematic diagram of a stacked power amplifier according to another embodiment.

FIG. 5I is a schematic diagram of a stacked power amplifier according to another embodiment.

FIG. 6A is a perspective view of one embodiment of a module that operates with beamforming.

FIG. 6B is a cross-section of the module of FIG. 6A taken along the lines 6B-6B.

FIG. 7 is a schematic diagram of one embodiment of a mobile device.

FIG. 8A is a schematic diagram of one embodiment of a packaged module.

FIG. 8B is a schematic diagram of a cross-section of the packaged module of FIG. 8A taken along the lines 8B-8B.

FIG. 9A is a schematic diagram of a cross-section of another embodiment of a packaged module.

FIG. 9B is a perspective view of another embodiment of a packaged module.

DETAILED DESCRIPTION OF EMBODIMENTS

The following detailed description of certain embodiments presents various descriptions of specific embodiments. However, the innovations described herein can be embodied in a multitude of different ways, for example, as defined and covered by the claims. In this description, reference is made to the drawings where like reference numerals can indicate identical or functionally similar elements. It will be understood that elements illustrated in the figures are not necessarily drawn to scale. Moreover, it will be understood that certain embodiments can include more elements than illustrated in a drawing and/or a subset of the elements illustrated in a drawing. Further, some embodiments can incorporate any suitable combination of features from two or more drawings.

The International Telecommunication Union (ITU) is a specialized agency of the United Nations (UN) responsible for global issues concerning information and communication technologies, including the shared global use of radio spectrum.

The 3rd Generation Partnership Project (3GPP) is a collaboration between groups of telecommunications standard bodies across the world, such as the Association of Radio Industries and Businesses (ARIB), the Telecommunications Technology Committee (TTC), the China Communications Standards Association (CCSA), the Alliance for Telecommunications Industry Solutions (ATIS), the Telecommunications Technology Association (TTA), the European Telecommunications Standards Institute (ETSI), and the Telecommunications Standards Development Society, India (TSDSI).

Working within the scope of the ITU, 3GPP develops and maintains technical specifications for a variety of mobile communication technologies, including, for example, second generation (2G) technology (for instance, Global System for Mobile Communications (GSM) and Enhanced Data Rates for GSM Evolution (EDGE)), third generation (3G) technology (for instance, Universal Mobile Telecommunications System (UMTS) and High Speed Packet Access (HSPA)), and fourth generation (4G) technology (for instance, Long Term Evolution (LTE) and LTE-Advanced).

The technical specifications controlled by 3GPP can be expanded and revised by specification releases, which can span multiple years and specify a breadth of new features and evolutions.

In one example, 3GPP introduced carrier aggregation (CA) for LTE in Release 10. Although initially introduced with two downlink carriers, 3GPP expanded carrier aggregation in Release 14 to include up to five downlink carriers and up to three uplink carriers. Other examples of new features and evolutions provided by 3GPP releases include, but are not limited to, License Assisted Access (LAA), enhanced LAA (eLAA), Narrowband Internet of things (NB-IOT), Vehicle-to-Everything (V2X), and High Power User Equipment (HPUE).

3GPP introduced Phase 1 of fifth generation (5G) technology in Release 15, and introduced Phase 2 of 5G technology in Release 16. Subsequent 3GPP releases will further evolve and expand 5G technology. 5G technology is also referred to herein as 5G New Radio (NR).

5G NR supports or plans to support a variety of features, such as communications over millimeter wave spectrum, beamforming capability, high spectral efficiency waveforms, low latency communications, multiple radio numerology, and/or non-orthogonal multiple access (NOMA). Although such RF functionalities offer flexibility to networks and enhance user data rates, supporting such features can pose a number of technical challenges.

The teachings herein are applicable to a wide variety of communication systems, including, but not limited to, communication systems using advanced cellular technologies, such as LTE-Advanced, LTE-Advanced Pro, and/or 5G NR.

FIG. 1 is a schematic diagram of one example of a communication network 10. The communication network 10 includes a macro cell base station 1, a small cell base station 3, and various examples of user equipment (UE), including a first mobile device 2 a, a wireless-connected car 2 b, a laptop 2 c, a stationary wireless device 2 d, a wireless-connected train 2 e, a second mobile device 2 f, and a third mobile device 2 g.

Although specific examples of base stations and user equipment are illustrated in FIG. 1, a communication network can include base stations and user equipment of a wide variety of types and/or numbers.

For instance, in the example shown, the communication network 10 includes the macro cell base station 1 and the small cell base station 3. The small cell base station 3 can operate with relatively lower power, shorter range, and/or with fewer concurrent users relative to the macro cell base station 1. The small cell base station 3 can also be referred to as a femtocell, a picocell, or a microcell. Although the communication network 10 is illustrated as including two base stations, the communication network 10 can be implemented to include more or fewer base stations and/or base stations of other types.

Although various examples of user equipment are shown, the teachings herein are applicable to a wide variety of user equipment, including, but not limited to, mobile phones, tablets, laptops, IoT devices, wearable electronics, customer premises equipment (CPE), wireless-connected vehicles, wireless relays, and/or a wide variety of other communication devices. Furthermore, user equipment includes not only currently available communication devices that operate in a cellular network, but also subsequently developed communication devices that will be readily implementable with the inventive systems, processes, methods, and devices as described and claimed herein.

The illustrated communication network 10 of FIG. 1 supports communications using a variety of cellular technologies, including, for example, 4G LTE and 5G NR. In certain implementations, the communication network 10 is further adapted to provide a wireless local area network (WLAN), such as WiFi. Although various examples of communication technologies have been provided, the communication network 10 can be adapted to support a wide variety of communication technologies.

Various communication links of the communication network 10 have been depicted in FIG. 1. The communication links can be duplexed in a wide variety of ways, including, for example, using frequency-division duplexing (FDD) and/or time-division duplexing (TDD). FDD is a type of radio frequency communications that uses different frequencies for transmitting and receiving signals. FDD can provide a number of advantages, such as high data rates and low latency. In contrast, TDD is a type of radio frequency communications that uses about the same frequency for transmitting and receiving signals, and in which transmit and receive communications are switched in time. TDD can provide a number of advantages, such as efficient use of spectrum and variable allocation of throughput between transmit and receive directions.

In certain implementations, user equipment can communicate with a base station using one or more of 4G LTE, 5G NR, and WiFi technologies. In certain implementations, enhanced license assisted access (eLAA) is used to aggregate one or more licensed frequency carriers (for instance, licensed 4G LTE and/or 5G NR frequencies), with one or more unlicensed carriers (for instance, unlicensed WiFi frequencies).

As shown in FIG. 1, the communication links include not only communication links between UE and base stations, but also UE to UE communications and base station to base station communications. For example, the communication network 10 can be implemented to support self-fronthaul and/or self-backhaul (for instance, as between mobile device 2 g and mobile device 2 f).

The communication links can operate over a wide variety of frequencies. In certain implementations, communications are supported using 5G NR technology over one or more frequency bands that are less than 6 Gigahertz (GHz) and/or over one or more frequency bands that are greater than 6 GHz. For example, the communication links can serve Frequency Range 1 (FR1), Frequency Range 2 (FR2), or a combination thereof. In one embodiment, one or more of the mobile devices support a HPUE power class specification.

In certain implementations, a base station and/or user equipment communicates using beamforming. For example, beamforming can be used to focus signal strength to overcome path losses, such as high loss associated with communicating over high signal frequencies. In certain embodiments, user equipment, such as one or more mobile phones, communicate using beamforming on millimeter wave frequency bands which include 5G FR2. Thus, as used herein a millimeter wave signal can include traditional millimeter waves (30 GHz to 300 GHz) as well as upper centimeter wave frequencies in the range of 24 GHz to 30 GHz.

Different users of the communication network 10 can share available network resources, such as available frequency spectrum, in a wide variety of ways.

In one example, frequency division multiple access (FDMA) is used to divide a frequency band into multiple frequency carriers. Additionally, one or more carriers are allocated to a particular user. Examples of FDMA include, but are not limited to, single carrier FDMA (SC-FDMA) and orthogonal FDMA (OFDMA). OFDMA is a multicarrier technology that subdivides the available bandwidth into multiple mutually orthogonal narrowband subcarriers, which can be separately assigned to different users.

Other examples of shared access include, but are not limited to, time division multiple access (TDMA) in which a user is allocated particular time slots for using a frequency resource, code division multiple access (CDMA) in which a frequency resource is shared amongst different users by assigning each user a unique code, space-divisional multiple access (SDMA) in which beamforming is used to provide shared access by spatial division, and non-orthogonal multiple access (NOMA) in which the power domain is used for multiple access. For example, NOMA can be used to serve multiple users at the same frequency, time, and/or code, but with different power levels.

Enhanced mobile broadband (eMBB) refers to technology for growing system capacity of LTE networks. For example, eMBB can refer to communications with a peak data rate of at least 10 Gbps and a minimum of 100 Mbps for each user. Ultra-reliable low latency communications (uRLLC) refers to technology for communication with very low latency, for instance, less than 2 milliseconds. uRLLC can be used for mission-critical communications such as for autonomous driving and/or remote surgery applications. Massive machine-type communications (mMTC) refers to low cost and low data rate communications associated with wireless connections to everyday objects, such as those associated with Internet of Things (IoT) applications.

The communication network 10 of FIG. 1 can be used to support a wide variety of advanced communication features, including, but not limited to, eMBB, uRLLC, and/or mMTC.

FIG. 2A is a schematic diagram of one example of a communication link using carrier aggregation. Carrier aggregation can be used to widen bandwidth of the communication link by supporting communications over multiple frequency carriers, thereby increasing user data rates and enhancing network capacity by utilizing fragmented spectrum allocations.

In the illustrated example, the communication link is provided between a base station 21 and a mobile device 22. As shown in FIG. 2A, the communications link includes a downlink channel used for RF communications from the base station 21 to the mobile device 22, and an uplink channel used for RF communications from the mobile device 22 to the base station 21.

Although FIG. 2A illustrates carrier aggregation in the context of FDD communications, carrier aggregation can also be used for TDD communications.

In certain implementations, a communication link can provide asymmetrical data rates for a downlink channel and an uplink channel. For example, a communication link can be used to support a relatively high downlink data rate to enable high speed streaming of multimedia content to a mobile device, while providing a relatively slower data rate for uploading data from the mobile device to the cloud.

In the illustrated example, the base station 21 and the mobile device 22 communicate via carrier aggregation, which can be used to selectively increase bandwidth of the communication link. Carrier aggregation includes contiguous aggregation, in which contiguous carriers within the same operating frequency band are aggregated. Carrier aggregation can also be non-contiguous, and can include carriers separated in frequency within a common band or in different bands.

In the example shown in FIG. 2A, the uplink channel includes three aggregated component carriers f_(UL1), f_(UL2), and f_(UL3). Additionally, the downlink channel includes five aggregated component carriers f_(DL1), f_(DL2), f_(DL3), f_(DL4), and f_(DL5). Although one example of component carrier aggregation is shown, more or fewer carriers can be aggregated for uplink and/or downlink. Moreover, a number of aggregated carriers can be varied over time to achieve desired uplink and downlink data rates.

For example, a number of aggregated carriers for uplink and/or downlink communications with respect to a particular mobile device can change over time. For example, the number of aggregated carriers can change as the device moves through the communication network and/or as network usage changes over time.

FIG. 2B illustrates various examples of uplink carrier aggregation for the communication link of FIG. 2A. FIG. 2B includes a first carrier aggregation scenario 31, a second carrier aggregation scenario 32, and a third carrier aggregation scenario 33, which schematically depict three types of carrier aggregation.

The carrier aggregation scenarios 31-33 illustrate different spectrum allocations for a first component carrier f_(UL1), a second component carrier f_(UL2), and a third component carrier f_(UL3). Although FIG. 2B is illustrated in the context of aggregating three component carriers, carrier aggregation can be used to aggregate more or fewer carriers. Moreover, although illustrated in the context of uplink, the aggregation scenarios are also applicable to downlink.

The first carrier aggregation scenario 31 illustrates intra-band contiguous carrier aggregation, in which component carriers that are adjacent in frequency and in a common frequency band are aggregated. For example, the first carrier aggregation scenario 31 depicts aggregation of component carriers f_(UL1), f_(UL2), and f_(UL3) that are contiguous and located within a first frequency band BAND1.

With continuing reference to FIG. 2B, the second carrier aggregation scenario 32 illustrates intra-band non-continuous carrier aggregation, in which two or more components carriers that are non-adjacent in frequency and within a common frequency band are aggregated. For example, the second carrier aggregation scenario 32 depicts aggregation of component carriers f_(UL1), f_(UL2), and f_(UL3) that are non-contiguous, but located within a first frequency band BAND1.

The third carrier aggregation scenario 33 illustrates inter-band non-contiguous carrier aggregation, in which component carriers that are non-adjacent in frequency and in multiple frequency bands are aggregated. For example, the third carrier aggregation scenario 33 depicts aggregation of component carriers f_(UL1) and f_(UL2) of a first frequency band BAND1 with component carrier f_(UL3) of a second frequency band BAND2.

FIG. 2C illustrates various examples of downlink carrier aggregation for the communication link of FIG. 2A. The examples depict various carrier aggregation scenarios 34-38 for different spectrum allocations of a first component carrier f_(DL1), a second component carrier f_(DL2), a third component carrier f_(DL3), a fourth component carrier f_(DL4), and a fifth component carrier f_(DL5). Although FIG. 2C is illustrated in the context of aggregating five component carriers, carrier aggregation can be used to aggregate more or fewer carriers. Moreover, although illustrated in the context of downlink, the aggregation scenarios are also applicable to uplink.

The first carrier aggregation scenario 34 depicts aggregation of component carriers that are contiguous and located within the same frequency band. Additionally, the second carrier aggregation scenario 35 and the third carrier aggregation scenario 36 illustrates two examples of aggregation that are non-contiguous, but located within the same frequency band. Furthermore, the fourth carrier aggregation scenario 37 and the fifth carrier aggregation scenario 38 illustrates two examples of aggregation in which component carriers that are non-adjacent in frequency and in multiple frequency bands are aggregated. As a number of aggregated component carriers increases, a complexity of possible carrier aggregation scenarios also increases.

With reference to FIGS. 2A-2C, the individual component carriers used in carrier aggregation can be of a variety of frequencies, including, for example, frequency carriers in the same band or in multiple bands. Additionally, carrier aggregation is applicable to implementations in which the individual component carriers are of about the same bandwidth as well as to implementations in which the individual component carriers have different bandwidths.

Certain communication networks allocate a particular user device with a primary component carrier (PCC) or anchor carrier for uplink and a PCC for downlink. Additionally, when the mobile device communicates using a single frequency carrier for uplink or downlink, the user device communicates using the PCC. To enhance bandwidth for uplink communications, the uplink PCC can be aggregated with one or more uplink secondary component carriers (SCCs). Additionally, to enhance bandwidth for downlink communications, the downlink PCC can be aggregated with one or more downlink SCCs.

In certain implementations, a communication network provides a network cell for each component carrier. Additionally, a primary cell can operate using a PCC, while a secondary cell can operate using a SCC. The primary and secondary cells may have different coverage areas, for instance, due to differences in frequencies of carriers and/or network environment.

License assisted access (LAA) refers to downlink carrier aggregation in which a licensed frequency carrier associated with a mobile operator is aggregated with a frequency carrier in unlicensed spectrum, such as WiFi. LAA employs a downlink PCC in the licensed spectrum that carries control and signaling information associated with the communication link, while unlicensed spectrum is aggregated for wider downlink bandwidth when available. LAA can operate with dynamic adjustment of secondary carriers to avoid WiFi users and/or to coexist with WiFi users. Enhanced license assisted access (eLAA) refers to an evolution of LAA that aggregates licensed and unlicensed spectrum for both downlink and uplink.

FIG. 3A is a schematic diagram of one example of a downlink channel using multi-input and multi-output (MIMO) communications. FIG. 3B is schematic diagram of one example of an uplink channel using MIMO communications.

MIMO communications use multiple antennas for simultaneously communicating multiple data streams over common frequency spectrum. In certain implementations, the data streams operate with different reference signals to enhance data reception at the receiver. MIMO communications benefit from higher SNR, improved coding, and/or reduced signal interference due to spatial multiplexing differences of the radio environment.

MIMO order refers to a number of separate data streams sent or received. For instance, MIMO order for downlink communications can be described by a number of transmit antennas of a base station and a number of receive antennas for UE, such as a mobile device. For example, two-by-two (2×2) DL MIMO refers to MIMO downlink communications using two base station antennas and two UE antennas. Additionally, four-by-four (4×4) DL MIMO refers to MIMO downlink communications using four base station antennas and four UE antennas.

In the example shown in FIG. 3A, downlink MIMO communications are provided by transmitting using M antennas 43 a, 43 b, 43 c, . . . 43 m of the base station 41 and receiving using N antennas 44 a, 44 b, 44 c, . . . 44 n of the mobile device 42. Accordingly, FIG. 3A illustrates an example of m×n DL MIMO.

Likewise, MIMO order for uplink communications can be described by a number of transmit antennas of UE, such as a mobile device, and a number of receive antennas of a base station. For example, 2×2 UL MIMO refers to MIMO uplink communications using two UE antennas and two base station antennas. Additionally, 4×4 UL MIMO refers to MIMO uplink communications using four UE antennas and four base station antennas.

In the example shown in FIG. 3B, uplink MIMO communications are provided by transmitting using N antennas 44 a, 44 b, 44 c, . . . 44 n of the mobile device 42 and receiving using M antennas 43 a, 43 b, 43 c, . . . 43 m of the base station 41. Accordingly, FIG. 3B illustrates an example of n×m UL MIMO.

By increasing the level or order of MIMO, bandwidth of an uplink channel and/or a downlink channel can be increased.

MIMO communications are applicable to communication links of a variety of types, such as FDD communication links and TDD communication links.

FIG. 3C is schematic diagram of another example of an uplink channel using MIMO communications. In the example shown in FIG. 3C, uplink MIMO communications are provided by transmitting using N antennas 44 a, 44 b, 44 c, . . . 44 n of the mobile device 42. Additional a first portion of the uplink transmissions are received using M antennas 43 a 1, 43 b 1, 43 c 1, . . . 43 m 1 of a first base station 41 a, while a second portion of the uplink transmissions are received using M antennas 43 a 2, 43 b 2, 43 c 2, . . . 43 m 2 of a second base station 41 b. Additionally, the first base station 41 a and the second base station 41 b communication with one another over wired, optical, and/or wireless links.

The MIMO scenario of FIG. 3C illustrates an example in which multiple base stations cooperate to facilitate MIMO communications.

FIG. 4A is a schematic diagram of one example of a communication system 110 that operates with beamforming. The communication system 110 includes a transceiver 105, signal conditioning circuits 104 a 1, 104 a 2 . . . 104 an, 104 b 1, 104 b 2 . . . 104 bn, 104 m 1, 104 m 2 . . . 104 mn, and an antenna array 102 that includes antenna elements 103 a 1, 103 a 2 . . . 103 an, 103 b 1, 103 b 2 . . . 103 bn, 103 m 1, 103 m 2 . . . 103 mn.

Communications systems that communicate using millimeter wave carriers (for instance, 30 GHz to 300 GHz), centimeter wave carriers (for instance, 3 GHz to 30 GHz), and/or other frequency carriers can employ an antenna array to provide beam formation and directivity for transmission and/or reception of signals.

For example, in the illustrated embodiment, the communication system 110 includes an array 102 of m×n antenna elements, which are each controlled by a separate signal conditioning circuit, in this embodiment. As indicated by the ellipses, the communication system 110 can be implemented with any suitable number of antenna elements and signal conditioning circuits.

With respect to signal transmission, the signal conditioning circuits can provide transmit signals to the antenna array 102 such that signals radiated from the antenna elements combine using constructive and destructive interference to generate an aggregate transmit signal exhibiting beam-like qualities with more signal strength propagating in a given direction away from the antenna array 102.

In the context of signal reception, the signal conditioning circuits process the received signals (for instance, by separately controlling received signal phases) such that more signal energy is received when the signal is arriving at the antenna array 102 from a particular direction. Accordingly, the communication system 110 also provides directivity for reception of signals.

The relative concentration of signal energy into a transmit beam or a receive beam can be enhanced by increasing the size of the array. For example, with more signal energy focused into a transmit beam, the signal is able to propagate for a longer range while providing sufficient signal level for RF communications. For instance, a signal with a large proportion of signal energy focused into the transmit beam can exhibit high effective isotropic radiated power (EIRP).

In the illustrated embodiment, the transceiver 105 provides transmit signals to the signal conditioning circuits and processes signals received from the signal conditioning circuits. As shown in FIG. 4A, the transceiver 105 generates control signals for the signal conditioning circuits. The control signals can be used for a variety of functions, such as controlling the gain and phase of transmitted and/or received signals to control beamforming.

FIG. 4B is a schematic diagram of one example of beamforming to provide a transmit beam. FIG. 4B illustrates a portion of a communication system including a first signal conditioning circuit 114 a, a second signal conditioning circuit 114 b, a first antenna element 113 a, and a second antenna element 113 b.

Although illustrated as included two antenna elements and two signal conditioning circuits, a communication system can include additional antenna elements and/or signal conditioning circuits. For example, FIG. 4B illustrates one embodiment of a portion of the communication system 110 of FIG. 4A.

The first signal conditioning circuit 114 a includes a first phase shifter 130 a, a first power amplifier 131 a, a first low noise amplifier (LNA) 132 a, and switches for controlling selection of the power amplifier 131 a or LNA 132 a. Additionally, the second signal conditioning circuit 114 b includes a second phase shifter 130 b, a second power amplifier 131 b, a second LNA 132 b, and switches for controlling selection of the power amplifier 131 b or LNA 132 b.

Although one embodiment of signal conditioning circuits is shown, other implementations of signal conditioning circuits are possible. For instance, in one example, a signal conditioning circuit includes one or more band filters, duplexers, and/or other components.

In the illustrated embodiment, the first antenna element 113 a and the second antenna element 113 b are separated by a distance d. Additionally, FIG. 4B has been annotated with an angle θ, which in this example has a value of about 90° when the transmit beam direction is substantially perpendicular to a plane of the antenna array and a value of about 0° when the transmit beam direction is substantially parallel to the plane of the antenna array.

By controlling the relative phase of the transmit signals provided to the antenna elements 113 a, 113 b, a desired transmit beam angle Θ can be achieved. For example, when the first phase shifter 130 a has a reference value of 0°, the second phase shifter 130 b can be controlled to provide a phase shift of about −2πf(d/v)cos Θ radians, where f is the fundamental frequency of the transmit signal, d is the distance between the antenna elements, ν is the velocity of the radiated wave, and π is the mathematic constant pi.

In certain implementations, the distance d is implemented to be about ½λ, where λ is the wavelength of the fundamental component of the transmit signal. In such implementations, the second phase shifter 130 b can be controlled to provide a phase shift of about −π cos Θ radians to achieve a transmit beam angle Θ.

Accordingly, the relative phase of the phase shifters 130 a, 130 b can be controlled to provide transmit beamforming. In certain implementations, a baseband processor and/or a transceiver (for example, the transceiver 105 of FIG. 4A) controls phase values of one or more phase shifters and gain values of one or more controllable amplifiers to control beamforming.

FIG. 4C is a schematic diagram of one example of beamforming to provide a receive beam. FIG. 4C is similar to FIG. 4B, except that FIG. 4C illustrates beamforming in the context of a receive beam rather than a transmit beam.

As shown in FIG. 4C, a relative phase difference between the first phase shifter 130 a and the second phase shifter 130 b can be selected to about equal to −2πf(d/v)cos Θ radians to achieve a desired receive beam angle Θ. In implementations in which the distance d corresponds to about ½λ, the phase difference can be selected to about equal to −π cos Θ radians to achieve a receive beam angle Θ.

Although various equations for phase values to provide beamforming have been provided, other phase selection values are possible, such as phase values selected based on implementation of an antenna array, implementation of signal conditioning circuits, and/or a radio environment.

FIG. 5A is a schematic diagram of a stacked power amplifier 200 according to one embodiment. The stacked power amplifier 200 includes a first power amplifier 191 and a second power amplifier 192.

As shown in FIG. 5A, the first power amplifier 191 operates to amplify a first RF input signal RF_(IN1) received at an input to generate a first RF output signal RF_(OUT1) at an output. Additionally, the second power amplifier 192 operates to amplify a second RF input signal RF_(IN2) received at an input to generate a second RF output signal RF_(OUT2) at an output. Although shown as including a single stage, the first power amplifier 191 and/or the second power amplifier 192 can be implemented using multiple stages.

In certain implementations, the first RF input signal RF_(IN1) and the second RF input signal RF_(IN2) correspond to RF signals of two separate RF transmission channels for beamforming. Accordingly, in certain implementations, the stacked power amplifier 200 is included in a mobile device or other RF communication system that operates with beamforming for enhanced transmit capability.

The stacked power amplifier 200 receives a power low supply voltage V1 (for instance, ground or a negative supply) and a power high supply voltage V2 (for instance, a positive supply) for powering the stacked power amplifier 200.

In the illustrated embodiment, the first power amplifier 191 and the second power amplifier 192 are arranged in a stack between the power high supply voltage V2 and the power low supply voltage V1. Thus, a positive supply terminal or input of the first power amplifier 191 is connected to the power high supply voltage V2, a negative supply terminal of the first power amplifier 191 is connected to a positive supply terminal of the second power amplifier 192, and a negative supply terminal of the second power amplifier 192 is connected to the power low supply voltage V1.

By powering the first power amplifier 191 and the second power amplifier 192 in this manner, DC current is reused. This in turn leads to lower power dissipation, reduced heat generation, and/or extended battery life in mobile applications.

Although the illustrated embodiment includes two power amplifiers that have been stacked for DC current reuse, the teachings herein are also applicable to stacked power amplifiers in which three or more power amplifiers have been stacked.

FIG. 5B is a schematic diagram of a stacked power amplifier 220 according to another embodiment. The stacked power amplifier 220 includes a first amplification field-effect transistor (FET) 211, a second FET 212, a first cascode FET 213 (biased by a first cascode gate bias voltage V_(CG1)), a second cascode FET 214 (biased by a second cascode gate bias voltage V_(CG2)), a first choke inductor 215, a second choke inductor 216, and a decoupling capacitor 217.

The stacked power amplifier 220 illustrates one implementation of the stacked power amplifier 200 of FIG. 5A. However, the teachings herein are applicable to power amplifier circuitry implemented in a wide variety of ways.

As shown in FIG. 5B, the stacked power amplifier 220 is powered by a battery voltage V_(BATT) and ground. Although FIG. 5B depicts the stacked power amplifier 220 operating with a power high supply voltage corresponding to a battery voltage and with a power low supply voltage corresponding to ground, the stacked power amplifier 220 can be powered using a different power high supply voltage and/or a different power low supply voltage.

The stacked power amplifier 220 includes a first power amplifier that serves to amplify a first RF input signal RF_(IN1) to generate a first RF output signal RF_(OUT1). The first power amplifier is associated with the first amplification FET 211, the first cascode FET 213, and the first degeneration inductor 215. Additionally, the stacked power amplifier 220 further includes a second power amplifier that serves to amplify a second RF input signal RF_(IN2) to generate a second RF output signal RF_(OUT2). The second power amplifier is associated with the second amplification FET 212, the second cascode FET 214, and the second degeneration inductor 216.

Thus, the stacked power amplifier 220 includes two power amplifiers that are stacked with one another for DC current reuse. In particular, a DC bias current I_(DC) flows through both the first power amplifier and the second power amplifier, thereby reducing power consumption and leading to a corresponding reduction in heat dissipation and enhancement in battery life.

The stacked power amplifier 220 includes the decoupling capacitor 217 for reducing variation in voltage of a virtual power supply node between the first power amplifier and the second power amplifier. For example, including the decoupling capacitor 217 aids in maintaining the voltage of the virtual power supply node at about half the difference between the battery voltage V_(BATT) and ground, or V_(BATT)/2.

In the illustrated embodiment, the first power amplifier and the second power amplifier are each implemented as a cascode FET power amplifier. However, the teachings herein are applicable to power amplifiers implemented using other types of amplifier topologies (including, but not limited to, common source amplifiers or common emitter amplifiers) as well as to other types of amplification devices (including, but not limited to, bipolar transistors). Moreover, although an implementation using n-type transistors is depicted, a stacked power amplifier can include p-type transistors, n-type transistors, or a combination of p-type transistors and n-type transistors. Accordingly, other implementations are possible.

FIG. 5C is a schematic diagram of a stacked power amplifier 230 according to another embodiment. The stacked power amplifier 230 includes a first choke inductor 215, a second choke inductor 216, a decoupling capacitor 217, an amplification n-type field-effect transistor (NFET) 221, an amplification p-type field effect transistor (PFET) 222.

The stacked power amplifier 230 illustrates another implementation of the stacked power amplifier 200 of FIG. 5A. However, the teachings herein are applicable to power amplifier circuitry implemented in a wide variety of ways.

As shown in FIG. 5C, the stacked power amplifier 230 is powered by a battery voltage V_(BATT) and ground. Although FIG. 5C depicts the stacked power amplifier 230 operating with a power high supply voltage corresponding to a battery voltage and with a power low supply voltage corresponding to ground, the stacked power amplifier 230 can be powered using a different power high supply voltage and/or a different power low supply voltage.

The stacked power amplifier 230 includes a first power amplifier that serves to amplify a first RF input signal RF_(IN1) to generate a first RF output signal RF_(OUT1). The first power amplifier is associated with the amplification NFET 221 and the first degeneration inductor 215. Additionally, the stacked power amplifier 230 further includes a second power amplifier that serves to amplify a second RF input signal RF_(IN2) to generate a second RF output signal RF_(OUT2). The second power amplifier is associated with the amplification PFET 222 and the second degeneration inductor 216.

Thus, the stacked power amplifier 230 includes two power amplifiers that are stacked with one another between a power high supply voltage and a power low supply voltage and that operate with a shared or common DC bias current I_(DC).

FIG. 5D is a schematic diagram of a stacked power amplifier 240 according to another embodiment. The stacked power amplifier 240 includes a first power amplifier 191, a second power amplifier 192, and a bias circuit 231.

As shown in FIG. 5D, the first power amplifier 191 operates to amplify a first RF input signal RF_(IN1) received at an input to generate a first RF output signal RF_(OUT1) at an output. Additionally, the second power amplifier 192 operates to amplify a second RF input signal RF_(IN2) received at an input to generate a second RF output signal RF_(OUT2) at an output.

With continuing reference to FIG. 5D, the bias circuit 231 controls a bias of the first power amplifier 191 and a bias of the second power amplifier 192 to control a DC bias current I_(DC) that flows from the power high supply voltage V₂ to the power low supply voltage V₁ through the first power amplifier 191 and the second power amplifier 192. In certain implementations, the first power amplifier 191 and the second power amplifier 192 each include a FET for providing RF signal amplification, and the bias circuit 231 sets a DC gate bias voltage level for a gate of each of the FETs.

FIG. 5E is a schematic diagram of a stacked power amplifier 251 according to another embodiment. In this embodiment, the stacked power amplifier 251 amplifies a first MIMO signal MIMO₁ and a second MIMO signal MIMO₂ to generate the first RF output signal RF_(OUT1) and the second RF output signal RF_(OUT2), respectively.

FIG. 5F is a schematic diagram of a stacked power amplifier 252 according to another embodiment. In this embodiment, the stacked power amplifier 252 amplifies a 5G signal and a 4G signal to generate the first RF output signal RF_(OUT1) and the second RF output signal RF_(OUT2), respectively.

FIG. 5G is a schematic diagram of a stacked power amplifier 253 according to another embodiment. In this embodiment, the stacked power amplifier 253 amplifies a first 5G signal 5G₁ and a second 5G signal 5G₂ to generate the first RF output signal RF_(OUT1) and the second RF output signal RF_(OUT2), respectively. The first 5G signal 5G₁ and the second 5G signal 5G₂ can be in the same 5G frequency band or in different 5G frequency bands.

FIG. 5H is a schematic diagram of a stacked power amplifier 254 according to another embodiment. In this embodiment, the stacked power amplifier 254 amplifies a first millimeter wave signal MMW₁ and a second millimeter wave signal MMW₂ to generate the first RF output signal RF_(OUT1) and the second RF output signal RF_(OUT2), respectively. In certain implementations, the first millimeter wave signal MMW₁ corresponds to a first 5G signal in FR2 and the second millimeter wave signal MMW₂ corresponds to a second 5G signal in FR2.

FIG. 5I is a schematic diagram of a stacked power amplifier 255 according to another embodiment. In this embodiment, the stacked power amplifier 255 amplifies a first carrier aggregation signal CA₁ and a second carrier aggregation signal CA₂ to generate the first RF output signal RF_(OUT1) and the second RF output signal RF_(OUT2), respectively.

FIG. 6A is a perspective view of one embodiment of a module 140 that operates with beamforming. FIG. 6B is a cross-section of the module 140 of FIG. 6A taken along the lines 6B-6B.

The module 140 includes a laminated substrate or laminate 141, a semiconductor die or IC 142, surface mount components 143, and an antenna array including patch antenna elements 151-166.

Although one embodiment of a module is shown in FIGS. 6A and 6B, the teachings herein are applicable to modules implemented in a wide variety of ways. For example, a module can include a different arrangement of and/or number of antenna elements, dies, and/or surface mount components. Additionally, the module 140 can include additional structures and components including, but not limited to, encapsulation structures, shielding structures, and/or wirebonds.

In the illustrated embodiment, the antenna elements 151-166 are formed on a first surface of the laminate 141, and can be used to transmit receive signals or to transmit and receive signals. Although the illustrated antenna elements 151-166 are rectangular, the antenna elements 151-166 can be shaped in other ways. Additionally, although a 4×4 array of antenna elements is shown, more or fewer antenna elements can be provided. Moreover, antenna elements can be arrayed in other patterns or configurations. Furthermore, in another embodiment, multiple antenna arrays are provided, such as separate antenna arrays for transmit and receive and/or multiple antenna arrays for MIMO and/or switched diversity.

In certain implementations, the antenna elements 151-166 are implemented as patch antennas. A patch antenna can include a planar antenna element positioned over a ground plane. A patch antenna can have a relatively thin profile and exhibit robust mechanical strength. In certain configurations, the antenna elements 151-166 are implemented as patch antennas with planar antenna elements formed on the first surface of the laminate 141 and the ground plane formed using an internal conductive layer of the laminate 141.

Although an example with patch antennas is shown, a modulate can include any suitable antenna elements, including, but not limited to, patch antennas, dipole antennas, ceramic resonators, stamped metal antennas, and/or laser direct structuring antennas.

In the illustrated embodiment, the IC 142 and the surface mount components 143 are on a second surface of the laminate 141 opposite the first surface.

The IC 142 includes signal conditioning circuits associated with the antenna elements 151-166 and including one or more stacked power amplifiers. For example, as depicted in FIG. 6B, the IC 142 can include a first stacked power amplifier 200 a for providing a first RF output signal to the antenna element 155 and a second RF output signal to the antenna element 156, and a second stacked power amplifier 200 b for providing a third RF output signal to the antenna element 157 and a fourth RF output signal to the antenna element 158.

In certain implementations, the IC 142 includes a serial interface, such as a mobile industry processor interface radio frequency front-end (MIPI RFFE) bus and/or inter-integrated circuit (I²C) bus that receives data for controlling the signal conditioning circuits, such as the amount of phase shifting provided by phase shifters. In another embodiment, the IC 142 includes signal conditioning circuits associated with the antenna elements 151-166 and an integrated transceiver.

The laminate 141 can be implemented in a variety of ways, and can include for example, conductive layers, dielectric layers, solder masks, and/or other structures. The number of layers, layer thicknesses, and materials used to form the layers can be selected based on a wide variety of factors, which can vary with application. The laminate 141 can include vias for providing electrical connections to signal feeds and/or ground feeds of the antenna elements 151-166. For example, in certain implementations, vias can aid in providing electrical connections between signaling conditioning circuits of the IC 142 and corresponding antenna elements.

The module 140 can be included in a communication system, such as a mobile phone or base station. In one example, the module 140 is attached to a phone board of a mobile phone.

FIG. 7 is a schematic diagram of one embodiment of a mobile device 800. The mobile device 800 includes a baseband system 801, a transceiver 802, a front end system 803, antennas 804, a power management system 805, a memory 806, a user interface 807, and a battery 808.

The mobile device 800 can be used communicate using a wide variety of communications technologies, including, but not limited to, 2G, 3G, 4G (including LTE, LTE-Advanced, and LTE-Advanced Pro), 5G NR, WLAN (for instance, WiFi), WPAN (for instance, Bluetooth and ZigBee), WMAN (for instance, WiMax), and/or GPS technologies.

The transceiver 802 generates RF signals for transmission and processes incoming RF signals received from the antennas 804. It will be understood that various functionalities associated with the transmission and receiving of RF signals can be achieved by one or more components that are collectively represented in FIG. 7 as the transceiver 802. In one example, separate components (for instance, separate circuits or dies) can be provided for handling certain types of RF signals.

The front end system 803 aids in conditioning signals transmitted to and/or received from the antennas 804. In the illustrated embodiment, the front end system 803 includes antenna tuning circuitry 810, power amplifiers (PAs) 811 (which include one or more stacked power amplifiers implemented in accordance with the teachings herein), low noise amplifiers (LNAs) 812, filters 813, switches 814, and signal splitting/combining circuitry 815. However, other implementations are possible.

For example, the front end system 803 can provide a number of functionalities, including, but not limited to, amplifying signals for transmission, amplifying received signals, filtering signals, switching between different bands, switching between different power modes, switching between transmission and receiving modes, duplexing of signals, multiplexing of signals (for instance, diplexing or triplexing), or some combination thereof.

In certain implementations, the mobile device 800 supports carrier aggregation, thereby providing flexibility to increase peak data rates. Carrier aggregation can be used for both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD), and may be used to aggregate a plurality of carriers or channels. Carrier aggregation includes contiguous aggregation, in which contiguous carriers within the same operating frequency band are aggregated. Carrier aggregation can also be non-contiguous, and can include carriers separated in frequency within a common band or in different bands.

The antennas 804 can include antennas used for a wide variety of types of communications. For example, the antennas 804 can include antennas for transmitting and/or receiving signals associated with a wide variety of frequencies and communications standards.

In certain implementations, the antennas 804 support MIMO communications and/or switched diversity communications. For example, MIMO communications use multiple antennas for communicating multiple data streams over a single radio frequency channel. MIMO communications benefit from higher signal to noise ratio, improved coding, and/or reduced signal interference due to spatial multiplexing differences of the radio environment. Switched diversity refers to communications in which a particular antenna is selected for operation at a particular time. For example, a switch can be used to select a particular antenna from a group of antennas based on a variety of factors, such as an observed bit error rate and/or a signal strength indicator.

The mobile device 800 can operate with beamforming in certain implementations. For example, the front end system 803 can include amplifiers having controllable gain and phase shifters having controllable phase to provide beam formation and directivity for transmission and/or reception of signals using the antennas 804. For example, in the context of signal transmission, the amplitude and phases of the transmit signals provided to the antennas 804 are controlled such that radiated signals from the antennas 804 combine using constructive and destructive interference to generate an aggregate transmit signal exhibiting beam-like qualities with more signal strength propagating in a given direction. In the context of signal reception, the amplitude and phases are controlled such that more signal energy is received when the signal is arriving to the antennas 804 from a particular direction. In certain implementations, the antennas 804 include one or more arrays of antenna elements to enhance beamforming.

The baseband system 801 is coupled to the user interface 807 to facilitate processing of various user input and output (I/O), such as voice and data. The baseband system 801 provides the transceiver 802 with digital representations of transmit signals, which the transceiver 802 processes to generate RF signals for transmission. The baseband system 801 also processes digital representations of received signals provided by the transceiver 802. As shown in FIG. 7, the baseband system 801 is coupled to the memory 806 of facilitate operation of the mobile device 800.

The memory 806 can be used for a wide variety of purposes, such as storing data and/or instructions to facilitate the operation of the mobile device 800 and/or to provide storage of user information.

The power management system 805 provides a number of power management functions of the mobile device 800. In certain implementations, the power management system 805 includes a PA supply control circuit that controls the supply voltages of the power amplifiers 811. For example, the power management system 805 can be configured to change the supply voltage(s) provided to one or more of the power amplifiers 811 to improve efficiency, such as power added efficiency (PAE).

As shown in FIG. 7, the power management system 805 receives a battery voltage from the battery 808. The battery 808 can be any suitable battery for use in the mobile device 800, including, for example, a lithium-ion battery.

FIG. 8A is a schematic diagram of one embodiment of a packaged module 900. FIG. 8B is a schematic diagram of a cross-section of the packaged module 900 of FIG. 8A taken along the lines 8B-8B.

The packaged module 900 includes radio frequency components 901, a semiconductor die 902, surface mount devices 903, wirebonds 908, a package substrate 920, and an encapsulation structure 940. The package substrate 920 includes pads 906 formed from conductors disposed therein. Additionally, the semiconductor die 902 includes pins or pads 904, and the wirebonds 908 have been used to connect the pads 904 of the die 902 to the pads 906 of the package substrate 920.

The semiconductor die 902 includes a stacked power amplifier 945, which can be implemented in accordance with one or more features disclosed herein.

The packaging substrate 920 can be configured to receive a plurality of components such as radio frequency components 901, the semiconductor die 902 and the surface mount devices 903, which can include, for example, surface mount capacitors and/or inductors. In one implementation, the radio frequency components 901 include integrated passive devices (IPDs).

As shown in FIG. 8B, the packaged module 900 is shown to include a plurality of contact pads 932 disposed on the side of the packaged module 900 opposite the side used to mount the semiconductor die 902. Configuring the packaged module 900 in this manner can aid in connecting the packaged module 900 to a circuit board, such as a phone board of a mobile device. The example contact pads 932 can be configured to provide radio frequency signals, bias signals, and/or power (for example, a power supply voltage and ground) to the semiconductor die 902 and/or other components. As shown in FIG. 8B, the electrical connections between the contact pads 932 and the semiconductor die 902 can be facilitated by connections 933 through the package substrate 920. The connections 933 can represent electrical paths formed through the package substrate 920, such as connections associated with vias and conductors of a multilayer laminated package substrate.

In some embodiments, the packaged module 900 can also include one or more packaging structures to, for example, provide protection and/or facilitate handling. Such a packaging structure can include overmold or encapsulation structure 940 formed over the packaging substrate 920 and the components and die(s) disposed thereon.

It will be understood that although the packaged module 900 is described in the context of electrical connections based on wirebonds, one or more features of the present disclosure can also be implemented in other packaging configurations, including, for example, flip-chip configurations.

FIG. 9A is a schematic diagram of a cross-section of another embodiment of a packaged module 950. The packaged module 950 includes a laminated package substrate 951 and a flip-chip die 952.

The laminated package substrate 951 includes a cavity-based antenna 958 associated with an air cavity 960, a first conductor 961, a second conductor 962. The laminated package substrate 951 further includes a planar antenna 959.

In certain implementations herein, a packaged module includes one or more integrated antennas. For example, the packaged module 950 of FIG. 9A includes the cavity-based antenna 958 and the planar antenna 959. By including antennas facing in multiple directions (including, but not limited to, directions that are substantially perpendicular to one another), a range of available angles for communications can be increased. Although one example of a packaged module with integrated antennas is shown, the teachings herein are applicable to modules implemented in a wide variety of ways.

FIG. 9B is a perspective view of another embodiment of a packaged module 1020. The module 1020 includes a laminated substrate 1010 and a semiconductor die 1012. The semiconductor die 1012 includes at least one stacked power amplifier 945. In certain implementations, the semiconductor die 1012 includes other circuitry 946, which can include, for example, variable gain amplifiers (VGAs), controllable phase shifters, switches, filters, biasing circuitry, and/or transceivers.

In the illustrated the embodiment, cavity-based antennas 1011 a-1011 p have been formed on an edge 1022 of the laminated substrate 1010. In this example, sixteen cavity-based antennas have been provided in a four-by-four (4×4) array. However, more or fewer antennas can be included and/or antennas can be arrayed in other patterns.

In another embodiment, the laminated substrate 1010 further include another antenna array (for example, a patch antenna array) formed on a second major surface of the laminated substrate 1010 opposite the first major surface 1021. Implementing the module 1020 aids in increasing a range of angles over which the module 1020 can communicate.

The module 1020 illustrates another embodiment of a module including an array of antennas that are controllable to provide beamforming. Implementing an array of antennas on a side of module aids in communicating at certain angles and/or directions that may otherwise be unavailable due to environmental blockage. Although an example with cavity-based antennas is shown, the teachings herein are applicable to implementations using other types of antennas.

Applications

Some of the embodiments described above have provided examples in connection with wireless devices or mobile phones. However, the principles and advantages of the embodiments can be used for any other systems or apparatus that have needs for power amplifiers.

Such power amplifiers can be implemented in various electronic devices. Examples of the electronic devices can include, but are not limited to, consumer electronic products, parts of the consumer electronic products, electronic test equipment, etc. Examples of the electronic devices can also include, but are not limited to, memory chips, memory modules, circuits of optical networks or other communication networks, and disk driver circuits. The consumer electronic products can include, but are not limited to, a mobile phone, a telephone, a television, a computer monitor, a computer, a hand-held computer, a personal digital assistant (PDA), a microwave, a refrigerator, an automobile, a stereo system, a cassette recorder or player, a DVD player, a CD player, a VCR, an MP3 player, a radio, a camcorder, a camera, a digital camera, a portable memory chip, a washer, a dryer, a washer/dryer, a copier, a facsimile machine, a scanner, a multi-functional peripheral device, a wrist watch, a clock, etc. Further, the electronic devices can include unfinished products.

CONCLUSION

Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise,” “comprising,” and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to.” The word “coupled”, as generally used herein, refers to two or more elements that may be either directly connected, or connected by way of one or more intermediate elements. Likewise, the word “connected”, as generally used herein, refers to two or more elements that may be either directly connected, or connected by way of one or more intermediate elements. Additionally, the words “herein,” “above,” “below,” and words of similar import, when used in this application, shall refer to this application as a whole and not to any particular portions of this application. Where the context permits, words in the above Detailed Description using the singular or plural number may also include the plural or singular number respectively. The word “or” in reference to a list of two or more items, that word covers all of the following interpretations of the word: any of the items in the list, all of the items in the list, and any combination of the items in the list.

Moreover, conditional language used herein, such as, among others, “may,” “could,” “might,” “can,” “e.g.,” “for example,” “such as” and the like, unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or states. Thus, such conditional language is not generally intended to imply that features, elements and/or states are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without author input or prompting, whether these features, elements and/or states are included or are to be performed in any particular embodiment.

The above detailed description of embodiments of the invention is not intended to be exhaustive or to limit the invention to the precise form disclosed above. While specific embodiments of, and examples for, the invention are described above for illustrative purposes, various equivalent modifications are possible within the scope of the invention, as those skilled in the relevant art will recognize. For example, while processes or blocks are presented in a given order, alternative embodiments may perform routines having steps, or employ systems having blocks, in a different order, and some processes or blocks may be deleted, moved, added, subdivided, combined, and/or modified. Each of these processes or blocks may be implemented in a variety of different ways. Also, while processes or blocks are at times shown as being performed in series, these processes or blocks may instead be performed in parallel, or may be performed at different times.

The teachings of the invention provided herein can be applied to other systems, not necessarily the system described above. The elements and acts of the various embodiments described above can be combined to provide further embodiments.

While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the disclosure. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the methods and systems described herein may be made without departing from the spirit of the disclosure. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the disclosure. 

What is claimed is:
 1. A mobile device comprising: a transceiver configured to generate a first radio frequency input signal and a second radio frequency input signal; and a front end system including a stacked power amplifier configured to receive power from a power high supply voltage and a power low supply voltage, the stacked power amplifier including a first power amplifier configured to amplify the first radio frequency input signal and a second power amplifier configured to amplify the second radio frequency input signal, the first power amplifier and the second power amplifier electrically connected in a stack between the power high supply voltage and the power low supply voltage and configured to operate with a shared DC bias current.
 2. The mobile device of claim 1 wherein the first power amplifier includes a positive supply terminal connected to the power high supply voltage and a negative supply terminal, and the second power amplifier includes a positive supply terminal connected to the negative supply terminal of the first power amplifier and a negative supply terminal connected to the power low supply voltage.
 3. The mobile device of claim 2 wherein the first power amplifier includes a first amplification field-effect transistor and a first cascode field-effect transistor connected in series between the negative supply terminal and the positive supply terminal of the first power amplifier, and the second power amplifier includes a second amplification field-effect transistor and a second cascode field-effect transistor connected in series between the negative supply terminal and the positive supply terminal of the second power amplifier.
 4. The mobile device of claim 3 wherein the first amplification field-effect transistor includes a gate configured to receive the first radio frequency input signal, and the second amplification field-effect transistor includes a gate configured to receive the second radio frequency input signal.
 5. The mobile device of claim 3 wherein the stacked power amplifier further includes a decoupling capacitor connected between a source of the second amplification field-effect transistor and the power low supply voltage.
 6. The mobile device of claim 3 wherein the stacked power amplifier further includes a first degeneration inductor connected between a drain of the first cascode field-effect transistor and a source of the second amplification field-effect transistor, and a second degeneration inductor connected between a drain of the second cascode field-effect transistor and the power high supply voltage.
 7. The mobile device of claim 1 further comprising an antenna array including a first antenna configured to transmit a first radio frequency output signal provided by the first power amplifier and a second antenna configured to transmit a second radio frequency output signal provided by the second power amplifier.
 8. The mobile device of claim 7 wherein the antenna array is configured to radiate a transmit beam based on the first radio frequency output signal and the second radio frequency output signal.
 9. The mobile device of claim 1 wherein the first radio frequency input signal is a first multiple-input multiple-output signal and the second radio frequency input signal is a second multiple-input multiple-output signal.
 10. The mobile device of claim 1 wherein the first radio frequency input signal is a first carrier aggregation signal and the second radio frequency input signal is a second carrier aggregation signal.
 11. The mobile device of claim 1 wherein the first radio frequency input signal and the second radio frequency signal are each a fifth generation signal.
 12. The mobile device of claim 1 wherein the first radio frequency input signal is a fifth generation signal and the second radio frequency input signal is a fourth generation signal.
 13. The mobile device of claim 1 wherein the first radio frequency input signal is a first millimeter wave signal and the second radio frequency input signal is a second millimeter wave signal.
 14. A packaged module comprising: a package substrate; and a semiconductor die attached to the package substrate and including a stacked power amplifier configured to receive power from a power high supply voltage and a power low supply voltage, the stacked power amplifier including a first power amplifier configured to amplify a first radio frequency input signal and a second power amplifier configured to amplify a second radio frequency input signal, the first power amplifier and the second power amplifier electrically connected in a stack between the power high supply voltage and the power low supply voltage and configured to operate with a shared DC bias current.
 15. The packaged module of claim 14 wherein the first power amplifier includes a positive supply terminal connected to the power high supply voltage and a negative supply terminal, and the second power amplifier includes a positive supply terminal connected to the negative supply terminal of the first power amplifier and a negative supply terminal connected to the power low supply voltage.
 16. The packaged module of claim 14 further comprising an antenna array formed on the package substrate, the antenna array including a first antenna configured to transmit a first radio frequency output signal provided by the first power amplifier and a second antenna configured to transmit a second radio frequency output signal provided by the second power amplifier.
 17. The packaged module of claim 16 wherein the antenna array includes a plurality of patch antennas formed on a surface of the package substrate.
 18. The packaged module of claim 16 wherein the antenna array includes a plurality of edge-fired antennas formed on an edge of the package substrate.
 19. A method of radio frequency signal amplification in a mobile device, the method comprising: powering a stacked power amplifier with a power high supply voltage and a power low supply voltage; amplifying a first radio frequency input signal using a first power amplifier of the stacked power amplifier; amplifying a second radio frequency input signal using a second power amplifier of the stacked power amplifier, the first power amplifier and the second power amplifier electrically connected in a stack between the power high supply voltage and the power low supply voltage; and biasing the first power amplifier and the second power amplifier with a shared DC bias current.
 20. The method of claim 19 further comprising beamforming a transmit beam using an antenna array, including transmitting a first radio frequency output signal provided by the first power amplifier on a first antenna of the antenna array and transmitting a second radio frequency output signal provided by the second power amplifier on a second antenna of the antenna array. 